A charged particle beam device, such as a scanning electron microscope, detects, using a charged particle detector, a secondary charged particle released by irradiating a primary charged particle beam to a sample. In turn, by associating the irradiation position of the primary charged particle beam with the detected signal, the charged particle beam device can acquire an observation image of the sample at a high magnification.
Secondary charged particle can be roughly divided into two types: secondary electron and reflected electron. A certain type of scanning electron microscope includes a reflected electron detector that is disposed between an objective lens and a sample and detects a reflected electron. A reflected electron detector includes a reflected electron detection element that detects a reflected electron.
A charged particle beam device disclosed in PLT 1 includes at least two annular reflected electron detection elements, each of which includes a reflected electron detection unit that has a separate amplifier. According to PLT 1, a compositional image is acquired by selecting, from among the reflected electron detection elements included in the reflected electron detection unit, a reflected electron detection element disposed on the inner circumference side. Also, an unevenness image is acquired by selecting a detection element disposed on the outer circumference side.